diff --git a/server/index.ts b/server/index.ts
index ce97c6b9..f07756f3 100644
--- a/server/index.ts
+++ b/server/index.ts
@@ -121,7 +121,8 @@ export function createServer() {
       const { data, error } = await adminSupabase.auth.admin.listUsers({ email });
       if (error) {
         console.error("[API] listUsers error:", error);
-        return res.status(error.status ?? 500).json({ error: error.message || String(error) });
+        const errMsg = typeof error === "string" ? error : (error?.message || JSON.stringify(error));
+        return res.status((error as any)?.status ?? 500).json({ error: errMsg });
       }
 
       const user = (data as any)?.users?.[0] ?? null;